Spontaneous Spark: The Electrical Engine of the Sinoatrial Node

If you sever the spinal cord and completely disconnect the human heart from the brain, the heart does not stop beating. It continues to pump blood with perfect rhythm. This is because the heart possesses its own, completely independent electrical generator: the Sinoatrial (SA) Node. Located in the upper right chamber of the heart, the SA Node is a microscopic cluster of highly specialized pacema...